tps replaced code 63

[airwaybill]

Ok, been gone a while but i need some help and can't figure this one out.

I had some issues with my 88 f250 and it was parked for a while. Figured out that i had clogged injectors and some other small problems. Replaced a faulty injector and cleaned all that were in good condition. Replaced valve cover gaskets, upper intake gasket, degreased and painted the valve covers. Redid all wireloom and fixed any loose connectors. Removed damaged smog system and capped all hard emmision lines. Capped EGR valve and blocked it's vacuum line. Fixed any leaky vacuum lines and just plain cleaned 'er up.

Also hooked the O2 censor back up as it had not been reinstalled after the exhaust was changed.

It ran fantastic for about a week. Then all of a sudden the check engine light came back on. Read code 53 tp above voltage. Backprobed the connector side and it read that the voltage was 4.5 or stuck open. So replaced the TPS. Now it reads code 63, voltage is below minimum.

What the heck is going on? It only starts to code this way after it is up to normal operating temp. And if I shut it off when it's warm, it won't restart. If I let it cool for a few it starts back up and the code is gone.

Any clue?

 

[airwaybill]

Anyone have any thoughts?

 

[Alvin in AZ]

I can look up code-63 algorithm later in the E/E-D book but, what TPS voltage
you got at idle? Between .8 and 1.0v?

The idle and starting problems might be the IAC. I had three used ones and all
three acted both good and bad in different ways switching back and forth over
a period of weeks/days/minutes. If you've got one that is screwed together
then take it off and take it apart and clean it and read the coil resistance too.

My newest one was bad because of a low resistant coil, swapped a coil that
was within spec on it and it fixed all my idle problems. Don't remember off hand
what the resistance range is supposed to be but will get back here later with it.

Alvin in AZ

 

[fatherdoug]

http://www.fordtruckfanatics.com/forum/showthread.php?t=20951

Liated above is a thread with a link to another forum that was posted by user flaresidethunder(Junior) that solved my code 63 problem on an '89 F250. I also had a low voltage on the TPS, and adjusting the position of the TPS solved the problem, thanks to Junior.

 

[airwaybill]

I'll try the IAC but I'm not sure why that would give me a code on the TPS.

As far as adjusting the tp sensor. What two wires do i backprobe? The Haynes manual says the sig wire and return wire. When i do that it reads 4.5v all the time in KOEO test. This makes no sense when the code is saying the voltage is low not high on the TPS.

 

[Alvin in AZ]

I'll try the IAC but I'm not sure why that would give me a code on the TPS.

Because the symptoms point at one or both parts.

As far as adjusting the tp sensor. What two wires do i backprobe?

The two wires that give you about a 3/4volt reading.

Real important here too is for the voltage to be -very- smooth and stable
all the way across the whole range.

...or its resistance reading while it's unplugged.

"smooth and stable" readings + used potentiometer = does that exist?

They haven't gone together very often in my experience! :/

But I did buy a new Standard Motor Products TPS from Rockauto and it
was for-sure a very smooth and stable acting device. Didn't fix all the
unstable-idle-problems by itself tho, it was a combination of the new TPS
and the cleaned-and-repaired IAC that did the trick.

The Haynes manual says the sig wire and return wire. When i do that it reads
4.5v all the time in KOEO test. This makes no sense when the code is saying
the voltage is low not high on the TPS.

It's obvious as anything you're either reading the wrong two wires or your
reading them without 'em being hooked up in the circuit and so the circuit
reading is "open" and not "loaded" like it should be. You tell me which.

-------------------------

My old scanner quit working for me (software trouble) or I'd scan a picture
of the jumpers I made from the parts truck wires.

...ascii it is then.

>-----------------|----->
>-----------|----------->
>-----|----------------->

> = female socket
> = male socket
| = twisted wires and soldered + they form a place to clip the meter.

* Don't let the meter clips or soldered connections touch or you *
* might "let the smoke out" of some component inside the EEC! *

Alvin in AZ

 

[airwaybill]

Appreciate all of that Alvin! I will try to read again. I was thinking wrong wires too, but you want to believe what you read

I'll try those things and report back.

 

[O'Rattlecan]

If all else fails, try unhooking the battery and letting the computer reset itself.

Ryan

 

[fatherdoug]

I'll try the IAC but I'm not sure why that would give me a code on the TPS.

As far as adjusting the tp sensor. What two wires do i backprobe? The Haynes manual says the sig wire and return wire. When i do that it reads 4.5v all the time in KOEO test. This makes no sense when the code is saying the voltage is low not high on the TPS.

The article referenced above says to backprobe the gray with white stripe wire, and the gray with red stripe wire, or the middle and bottom wire. Following the procedure listed above, I increased the TPS sensor voltage from .89 volts to .95 volts, which was enough to solve a hestitation problem when accelerating off of idle.

 

[Alvin in AZ]

The article referenced above says to back probe the gray with white stripe
wire, and the gray with red stripe wire, or the middle and bottom wire.

Following the procedure listed above, I increased the TPS sensor voltage from
.89 volts to .95 volts, which was enough to solve a hesitation problem when
accelerating off of idle.

Cool your wire colors are better.

Just found my notes they use the TPS's wires and they say...
"green to black, red is power"
Guessing...
green=(+) Black=(-) red=5v
{shrug}

Butthead in AZ

 

[airwaybill]

Ok, checked the voltage on the Tps and it's .94 volts and goes to 4.5 volt at WOT. Smooth across the range as far as i can tell with a analog voltmeter.

Pulled the IAC, cleaned it and put it back. Truck ran fine through warm up and drove it around quite a bit. Parked it and it would not start. So, bad IAC? or something else? I did not check the coil resistance as i ran out of daylight. I will check it later when i have time. Just wanted to get some opinions.

 

[airwaybill]

Oh and the code 63 is back

 

[fatherdoug]

Did you try adjusting the TPS to raise the voltage as the article suggests? If I remember right, 0.94 volts is right on the bottom edge of acceptable.

Sorry, can't help with the IAC or starting problem.

 

[airwaybill]

It's an analog meter and i'm using paper clips so i'm sure it's good. That still doesn't explain why it won't start when warm.

 

[flareside_thunder]

The no start after warmup leaves me thinking the TFI module may be bad....Yours should be mounted on the distributor.

 

[airwaybill]

Had it tested a few months ago and it was fine.

 

[Alvin in AZ]

The no start after warmup leaves me thinking the TFI module
may be bad....Yours should be mounted on the distributor.

x2 Sounds like a good one to me too, Fireside.
Wasn't gonna say so but then that next post popped up... LOL

---------------------

Anybody ever grind-down a socket to fit down inside those recesses?
That's what I need to do again pretty soon.

I bought some 3/4" long "threaded stand offs" that are the same thread
(m4x.7). They'll act like really-tall hex headed screws.

Got 'em from McMaster-Carr
93655A715

Hmmm... couldn't figure out a way to post McMC's whole page here's a picture...
http://www.mcmaster.com/param/images/Stacers/malefemthread.gif

Butthead in AZ

 

[airwaybill]

Wouldn't I get a code on the TFI? I'll check it again. But It has been checked and sat since I checked it. Not sure why it would just go bad like that. Just don't want to take stabs in the dark. This is getting expensive!

 

[smokey]

Tfi can go bad with no codes. Had one flake out and it never completely died but caused all kinds of drivability issues. Threw codes for other stuff that all speced out fine. Swapped a new one and all was fine. The old one tested ok but was faulty when it hit a certain temp.

 

[Alvin in AZ]

The old one tested ok but was faulty when it hit a certain temp.

x2 There it it!

I've read over and over how you have to make 'em test TFI's several times in a
row, so they heat up, to catch that common fault.

My Bronco lately has been hard starting when it's hot but still starts good cold
and so have been wondering if the TFI is getting weak. I carry a spare TFI but
need to remember to get some heat-paste.

Alvin in AZ